1. Field of the Disclosure
The disclosure relates generally to a filter tuning probe for a radio frequency device. More particularly, the disclosure relates to a filter tuning probe for a radio frequency device having a locking device.
2. Related Art
With the increasing growth of wireless communications, the use of lower power radio frequency (RF) transmitters to fill in presently unserved areas is also increasing. Whether the application is broadcast TV, cellular phone service, wireless broadband access or many others, the availability of cost effective equipment for deployment of these lower power sites is critical. One of the key components for many of these sites will be the filter devices used on an output of the transmitters to maintain compliance with regulatory guidelines limiting the out-of-band signal levels that may cause interference to other channels.
One of the desired features for cost effective, low power filter design is the ability to use common components in multiple channel applications and for components in other various frequency applications. For example, using the same enclosure for the filter cavities over a wide band of frequencies such as the UHF TV band (470 MHz-860 MHz), VHF frequency bands, FM frequency bands, wireless frequency bands, GHz frequency bands, and the like. However, for each individual channel within that band, the optimum physical size is not constant. Therefore, some adjustment must be available to allow tuning of the cavities for each specific channel and application. Additionally, it is desirable that a filter have the capability of being retuned for a different channel if the application it is being used for changes in the future.
Typically, determination of the desired tuning probe penetration depth is an iterative process. Present state of the art utilizes flexible contact devices such as watchband springs and contact finger stock. These devices can be both costly and require machining of support grooves and/or attachment hardware to assemble. These approaches require the use of custom designed tubing or rod materials for the tuning probe that substantially adds to the cost.
Accordingly, there is a need for cost effective manufacturing of these filters while maintaining compliance to out-of-band emissions.